In radiography, X-ray image detectors with round detector surface areas are widely used. These predominately involve X-ray image intensifiers whose output screen is captured with a camera.
An X-ray diagnostic device with an X-ray image intensifier chain is disclosed in DE9755764C2, in which it is provided to display the round camera image on a monitor. The display can be rotated about the center of the image by a user.
An X-ray diagnostic device with an X-ray image intensifier chain is disclosed in DE4224615B4, in which it is provided to achieve the rotation of the round camera image such that the camera is rotated, controlled by a motor. The display of the rotated image can be displayed without image-processing procedures on an image-processing computer.
Conventional X-ray image intensifiers have circular inlet windows with a radiation-sensitive circular surface area of, for example, 213 mm (9-inch image intensifier) or 293 mm (12-inch image intensifier) and a greatly reduced output image.
For many reasons, there is the desire to equip radiography installations, which were earlier equipped with an X-ray image intensifier, with a solid-body X-ray image detector. The reasons include, for example, a lower installation volume, the insensitivity relative to external magnetic fields, and the lack of geometric distortion, like the curvature of the image field occurring in the edge region in image intensifiers.
In one aspect, the present disclosure provides a solid-body X-ray image detector. The detector comprises a substrate comprising a single, uncut, substantially circular silicon wafer made from crystalline silicon, a plurality of detectors on the substrate, and a scintillator arranged on the substrate. A circular detector surface area includes the surface area of the substrate, excluding a narrow edge region.
In one embodiment, the substrate includes a two-dimensional sensor fabricated using charged-coupled device (CCD) or complementary metal-oxide semiconductor (CMOS) technology. In another embodiment, the plurality of detector pixels are located adjacent to a semi-circular, ring-shaped read-out region adjacent to the silicon wafer.
In another embodiment, the diameter of the detector surface area is about 195 mm. In other embodiments, the detector surface area may be about 295 mm in diameter.
In certain embodiments, the plurality of detector pixels substantially cover the circular detector surface area. In another embodiment, the narrow edge region surrounding the circular detector surface area measures about 5 mm in the radial direction.
According to another aspect, the present disclosure provides a method for manufacturing a solid-body X-ray image detector. The method comprises providing a single, uncut, substantially circular silicon wafer made from crystalline silicon, arranging a plurality of detector pixels on the wafer, and depositing a scintillator over the plurality of detector pixels. In one embodiment, arranging the plurality of detector pixels comprises arranging a two-dimensional sensor fabricated using CCD or CMOS technology. In another embodiment, a semi-circular, ring-shaped read-out region is arranged adjacent to the silicon wafer in the radial direction.
In some embodiments, the silicon wafer is about 200 mm in diameter. In other embodiments, the silicon wafer is about 300 mm in diameter.
In another embodiment, the plurality of detector pixels substantially covers the wafer. In some embodiments, the plurality of detector pixels cover the entire first side of the wafer except for a narrow edge region. In certain embodiments, the narrow edge region measures about 5 mm in the radial direction.